The users who directly upgrade to Windows 10, 7 or 8.1 may not face the same error. It is an activation error which states that the server determined the keys to be invalid or keys are blocked. Apart from several errors the most common error that the new Windows 10 users are receiving is the Error Code 0xC004C003. Microsoft is trying hard to fix those errors. Most of the users have taken the benefit of Free Upgrade to Windows 10, 8.1 and 7? Well, that’s great, but with the new Windows 10, users are facing various errors and bugs.
